As the title says, this post is just a filtering of todays proggit. Namely the posts that caught my interest.
Posts on in-process databases:
Post on OS memory management:
I’ve decided to learn Go. Not the board game, but the programming language. Why? I’ve been wanting to learn a systems programming language for a while, but have so far avoided picking up my brick of a C++ manual.
If Go can really replace C++ when writing e.g. a high performancee server (I don’t know enough to say that yet), then that is good news! For starters I’m doing
Hadn’t heard about The Wikileaks Spy Files before today. This post is a follow up on the previous post on surveillance software. Who knows, maybe I have some of that on my computer as I’m typing this. Better smile and wave at the webcam 
Reporters without borders (RSF) have a website on topic: surveillance.rsf.org/en/. The topic being malware that can be used to spy on you through your own computer. It is frightening and intriguing at the same time.
I just read this blog post by Scott Hanselman (I’m a phony. Are you?), and it was a bit of a group therapy moment. It’s nice to know that you’re not alone in something!
This video was mentioned on highscalability.com, so I thought I’d have a look. Knowning this stuff is useful when you’re in the business of delivering large amounts of geographical data to a large amount of clients.
C10M = 10 million concurrent requests.
This is work in progress…
http://geocommons.com/
http://www.giscloud.com/
http://cartodb.com/
http://www.google.com/drive/start/apps.html#fusiontables
http://tables.googlelabs.com/
http://cloudmade.com/
http://mapbox.com/
http://mapquest.com
http://maps.google.com
This post is very Denmark-specific. I was annoyed that downloading environmental data from the ministry of the environment was so cumbersome.
Long story made short, here are download URLs for environmental data:
| Dataset | URL |
|---|---|
| Kirkebyggelinjer | KIRKEBYGGELINJER_SHAPE.zip |
| Skovbyggelinjer | SKOVBYGGELINJER_SHAPE.zip |
| Åbeskyttelseslinjer | AA_BES_LINJER_SHAPE.zip |
| Søbeskyttelseslinjer | SOE_BES_LINJER_SHAPE.zip |
| EF Fuglebeskyttelsesområder | EF_FUGLE_BES_OMR_SHAPE.zip |
| EF Habitatområder | EF_HABITAT_OMR_SHAPE.zip |
| RAMSAR-områder | RAMSAR_OMR_SHAPE.zip |
| Naturvildtreservat | NATUR_VILDT_RESERVAT_SHAPE.zip |
There are more. I’ll add them when I have the time. Why there ministry homepage does not provide direct links like this is beyond me.
The symbol ≤ denotes a generalization of “less than or equal”, and it defines either a partial or total ordering over a set P (in the table below a,b ∈ P):
| Constraint | (Non-strict) partial order | (Non-strict) total order |
|---|---|---|
| Reflexivity: a ≤ a | x | x |
| Antisymmetry: if a ≤ b and b ≤ a then a = b | x | x |
| Transitivity: if a ≤ b and b ≤ c then a ≤ c | x | x |
| Totality: either a ≤ b or b ≤ a | x |
The symbol < denotes a generalization of “less than”, and it defines either a partial or total ordering over a set P (in the table below a,b ∈ P):
| Constraint | (Strict) partial order | (Strict) total order |
|---|---|---|
| Irreflexivity: ¬(a < a) | x | x |
| Asymmetry: if a < b then ¬(b < a) | x | x |
| Transitivity: if a < b and b < c then a < c | x | x |
| Totality: either a < b or b < a | x |
Note the difference between asymmetry and antisymmetry.
| Type of relation | Constraint |
|---|---|
| Asymmetric relation | if a < b then ¬(b < a) |
| Antisymmetric relation (two equivalent definitions) |
if a ≤ b and b ≤ a then a = b |
| if a ≠ b then ¬(b ≤ a) |
Simple. This works.